Static file 404 not found Django - django

Question

I can't retrieve a static file from my template
I have the my project structure as follow:
.
├── db.sqlite3
├── gr_recommendation
│   ├── __init__.py
│   ├── __init__.pyc
│   ├── settings.py
│   ├── settings.pyc
│   ├── urls.py
│   ├── urls.pyc
│   ├── wsgi.py
│   └── wsgi.pyc
├── manage.py
└── recom
├── admin.py
├── admin.pyc
├── apps.py
├── __init__.py
├── __init__.pyc
├── migrations
│   └── __init__.py
├── models.py
├── models.pyc
├── static
│   ├── recom
│   │   └── style.css
│   └── style.css
├── templates
│   └── recom
│   └── index.html
├── tests.py
├── urls.py
├── urls.pyc
├── views.py
└── views.pyc
In settings.py I have the basic configuration:
DEBUG = True
INSTALLED_APPS = [
'django_cassandra_engine',
'django.contrib.admin',
'django.contrib.auth',
'django.contrib.contenttypes',
'django.contrib.sessions',
'django.contrib.messages',
'django.contrib.staticfiles',
'recom',
]
STATIC_URL = '/static/'
According to the documentation:
Serving the files
In addition to these configuration steps, you’ll also need to actually serve the static files.
During development, if you use django.contrib.staticfiles, this will be done automatically by runserver when DEBUG is set to True (see django.contrib.staticfiles.views.serve()).
My index.html template there is the following code:
{% load staticfiles %}
<link rel="stylesheet" type="text/css" href="{% static 'recom/style.css' %}" />
<h1>{{book.title}}</h1>
When I go in the application path /recom the html is showed without the css rules and I have the following error in the server console:
[25/Jan/2016 13:30:59] "GET /static/recom/style.css HTTP/1.1" 404 2126
If a try to access to http://my_server_ip:8000/static/recom/style.css
I have a 404 error.
Can anyone help me to make it works?